Feed result of equation back into itself? How?

Hello,

I've attached my mathcad document and it explains what I am trying to do.

I have two equations, A and B.

Equation A determines the length of a crack in a material specimen after the specimen has been loaded a distinct number of times. This is based on several variables, one of them being the initial length of the crack.

So after one cycle, I can determine how much this crack grew. I can then determine the residual strength of the material based on this new crack size.

What I need to do, is make a plot that has residual strength (Equation B) in the y axis, and number of cycles (Equation A) in the X axis.

The process would look like this:

1 - Equation A calculates the final crack length in the specimen after ONE cycle (given an initial crack length value).

2 - Equation B takes this final crack length and calculates the residual strength.

3 - The residual strength is plotted in the 2D plot.

4 - This final crack length is then fed back into Equation A to determine how much it grows after ONE cycle.

5 - Repeat steps 2-4 until the residual strengh reaches zero.

How can I do this? I appreciate any help!

Attached is the workbook.